Cute game. the how to play image is a black square that stays in place even if you move and only goes out by time, maybe make it so it dissapears after the player accepts that they read it.
I collect cheese but it doesn't seem to change the cheese collected score, you can't recharge your weapon so i don't think there should be a limit to the ammo, also you could add coyote time to the jumps.
Good job on your first game, i wish you luck on your game dev journey.